CN108141824B - DRX and SPS for MTC using bundled transmissions - Google Patents

Abstract

In eMTC, channels may be bundled using repetition in multiple subframes. SPS and DRX for eMTC may not accommodate such repetitions, as repetitions of the bundled channel may only be partially in the DRX on duration. An apparatus solves this problem by: determining a DRX on-duration; determining a subframe set carrying bundled M-PDCCH candidates; and determining that the DRX on duration at least partially overlaps with a set of subframes of the bundled M-PDCCH. The apparatus then refrains from decoding the first bundled M-PDCCH candidate, or extending the DRX on duration to include the entire set of subframes. The apparatus may also determine DRX configuration parameters based on parameters of the bundled channels and process invalid subframes for SPS grants.

Description

DRX and SPS for MTC using bundled transmissions

Cross Reference to Related Applications

This application claims the benefit of U.S. provisional application No.62/246,569 entitled "DRX AND SPS FOR MTC WITH led transitions" filed 26/2015 AND U.S. patent application No.15/236,947 entitled "DRX AND SPS FOR MTC WITH led transitions" filed 8/2016, filed 15/2016, the entire contents of which are expressly incorporated herein by reference.

Technical Field

The present disclosure relates generally to communication systems, and more particularly to Discontinuous Reception (DRX) and semi-persistent scheduling (SPS) applied to Machine Type Communication (MTC).

Background

Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, and broadcasting. A typical wireless communication system may employ multiple-access techniques capable of supporting communication with multiple users by sharing the available system resources. Examples of such multiple-access techniques include Code Division Multiple Access (CDMA) systems, Time Division Multiple Access (TDMA) systems, Frequency Division Multiple Access (FDMA) systems, Orthogonal Frequency Division Multiple Access (OFDMA) systems, single carrier frequency division multiple access (SC-FDMA) systems, and time division synchronous code division multiple access (TD-SCDMA) systems.

These multiple access techniques have been employed in a variety of telecommunications standards to provide a common protocol that enables different wireless devices to communicate on a local, national, regional, and even global level. One example telecommunication standard is Long Term Evolution (LTE). LTE is an enhanced set of Universal Mobile Telecommunications System (UMTS) mobile standards promulgated by the third generation partnership project (3 GPP). LTE is designed to support mobile broadband access with improved spectral efficiency, reduced cost, and improved service, using OFDMA on the downlink, SC-FDMA on the uplink, and multiple-input multiple-output (MIMO) antenna technology. However, as the demand for mobile broadband access continues to grow, there is a need for further improvements in LTE technology. These improvements are also applicable to other multiple access techniques and telecommunications standards employing these techniques.

Discontinuous Reception (DRX) is a technique that may be used in wireless communications to conserve battery life of a User Equipment (UE). To perform DRX, the UE and the network may negotiate an awake window period during which the UE powers on a receiver to allow data transmission with the network. Outside the awake window period, the UE may turn the receiver off and enter a low or zero power state to conserve battery life.

In enhanced machine type communication (eMTC), channels may be bundled in the time domain using repetitions in multiple subframes. Current semi-persistent scheduling (SPS) and DRX for MTC or eMTC may not be suitable for such repetition.

Disclosure of Invention

The following presents a simplified summary of one or more aspects in order to provide a basic understanding of such aspects. This summary is not an extensive overview of all contemplated aspects, and is intended to neither identify key or critical elements of all aspects nor delineate the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form as a prelude to the more detailed description that is presented later.

In eMTC, channels may be bundled, e.g., repeated using multiple subframes. For example, the control channel may use a repetition level of 2 times every 2 subframes, 4 times every 4 subframes, etc. Data channels may also be bundled with dynamic length. Sometimes, the starting subframe of the control channel may not be aligned with the radio frame boundary.

Current SPS and DRX for MTC/eMTC may not be suitable for such repetition. For example, repetitions for bundled channels may fall partially within the DRX on duration and may fall partially outside the DRX on duration. Thus, the UE may turn on its receiver only to receive a portion of the subframes of the bonded channel.

The present disclosure addresses this problem by providing the following techniques to the UE: techniques for handling bundled channels that only partially overlap with a DRX on duration, and techniques for determining DRX configuration parameters based on the parameters of the bundled channels and handling invalid subframes for SPS grants.

In one aspect of the disclosure, methods, computer-readable media, and apparatuses are provided. The apparatus determines a DRX on duration and determines a set of subframes that carry a first bundled MTC physical downlink control channel (M-PDCCH) candidate, the set of subframes comprising a plurality of subframes. The apparatus determines that the DRX on duration at least partially overlaps with the set of subframes and performs one of: (a) refraining from decoding the first bundled M-PDCCH candidate, (b) decoding the first bundled M-PDCCH candidate, or (c) extending the DRX on duration to include the entire set of subframes and decoding the first bundled M-PDCCH candidate carried in the set of subframes in the extended DRX on duration. For example, the apparatus may decode the first bundled M-PDDCH candidate if all of the plurality of subframes of the first bundled M-PDCCH candidate are located within the DRX on duration, and the apparatus may refrain from decoding the first bundled M-PDDCH candidate if at least one of the plurality of subframes of the first bundled M-PDDCH candidate are located outside the DRX on duration.

In another aspect of the disclosure, methods, computer-readable media, and apparatuses are provided. The apparatus determines a parameter of an M-PDCCH candidate monitored by a UE, receives an indication associated with a DRX configuration of the UE, and determines a DRX configuration parameter that is a function of the parameter and the indication of the M-PDCCH candidate. For example, the parameters of the bundled M-PDCCH may include a repetition level and/or the indication may include a number of subframes for which the UE should monitor PDCCH.

In another aspect of the disclosure, methods, computer-readable media, and apparatuses are provided. The apparatus receives an SPS grant for a set of subframes, the set of subframes including unavailable subframes, determines a subset of available subframes in the set of subframes, and adjusts reception or transmission during the set of subframes based on the subset of available subframes. For example, the apparatus may defer bundled transmissions scheduled for the unavailable subframe and for any subframes in the set of subframes that follow the unavailable subframe. As another example, the apparatus may discard bundled transmissions scheduled for the unavailable subframe or discard entire transmissions that will partially overlap with the unavailable subframe.

To the accomplishment of the foregoing and related ends, the one or more aspects comprise the features hereinafter fully described and particularly pointed out in the claims. The following description and the annexed drawings set forth in detail certain illustrative features of the one or more aspects. These features are indicative, however, of but a few of the various ways in which the principles of various aspects may be employed and the description is intended to include all such aspects and their equivalents.

Drawings

Fig. 1 is a diagram illustrating an example of a wireless communication system and an access network.

Fig. 2A, 2B, 2C, and 2D are diagrams illustrating LTE examples of a DL frame structure, a DL channel in the DL frame structure, an UL frame structure, and an UL channel in the UL frame structure, respectively.

Fig. 3 is a diagram illustrating an example of an evolved node b (enb) and a UE in an access network.

Fig. 4 is an example configuration of an M-PDCCH subframe and DRX on duration.

Fig. 5 is an example configuration of an M-PDCCH subframe and DRX on duration.

Fig. 6 is an example configuration of an M-PDCCH subframe and DRX on duration.

Fig. 7 is an example configuration of an M-PDCCH subframe and DRX on duration.

Fig. 8 is an example configuration of an M-PDCCH subframe and DRX on duration.

Fig. 9 is an example configuration of a CSI reference subframe and a DRX cycle.

Fig. 10 is a flow chart of a method of wireless communication.

Fig. 11 is a flow chart of a method of wireless communication.

Fig. 12 is a flow chart of a method of wireless communication.

Fig. 13 is a flow chart of a method of wireless communication.

Fig. 14 is a flow chart of a method of wireless communication.

Fig. 15 is a flow chart of a method of wireless communication.

Fig. 16 is a flow chart of a method of wireless communication.

Fig. 17 is a conceptual data flow diagram illustrating the data flow between different units/components in an exemplary apparatus.

Fig. 18 is a diagram illustrating an example of a hardware implementation of an apparatus employing a processing system.

Detailed Description

The detailed description set forth below in connection with the appended drawings is intended as a description of various configurations and is not intended to represent the only configurations in which the concepts described herein may be practiced. The detailed description includes specific details for the purpose of providing a thorough understanding of the various concepts. It will be apparent, however, to one skilled in the art that these concepts may be practiced without these specific details. In some instances, well-known structures and components are shown in block diagram form in order to avoid obscuring such concepts.

Several aspects of a telecommunications system will now be presented with reference to various apparatus and methods. These apparatus and methods will be described in the following detailed description and illustrated in the accompanying drawings by various blocks, components, circuits, processes, algorithms, etc. (collectively referred to as "elements"). These elements may be implemented using electronic hardware, computer software, or any combination thereof. Whether such elements are implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system.

For example, an element, or any portion of an element, or any combination of elements, may be implemented as a "processing system" that includes one or more processors. Examples of processors include microprocessors, microcontrollers, Graphics Processing Units (GPUs), Central Processing Units (CPUs), application processors, Digital Signal Processors (DSPs), Reduced Instruction Set Computing (RISC) processors, systems on chip (socs), baseband processors, Field Programmable Gate Arrays (FPGAs), Programmable Logic Devices (PLDs), state machines, gated logic, discrete hardware circuits, and other suitable hardware configured to perform the various functions described throughout this disclosure. One or more processors in the processing system may execute software. Software shall be construed broadly to mean instructions, instruction sets, code segments, program code, programs, subprograms, software modules, applications, software packages, routines, subroutines, objects, executables, threads of execution, procedures, functions, etc., whether referred to as software, firmware, middleware, microcode, hardware description language, or other terminology.

Accordingly, in one or more example embodiments, the functions described may be implemented in hardware, software, or any combination thereof. If implemented in software, the functions may be stored on or encoded on a computer-readable medium as one or more instructions or code. Computer readable media includes computer storage media. A storage media may be any available media that can be accessed by a computer. By way of example, and not limitation, such computer-readable media can comprise Random Access Memory (RAM), Read Only Memory (ROM), electrically erasable programmable ROM (eeprom), optical disk storage, magnetic disk storage or other magnetic storage devices, combinations of the above types of computer-readable media, or any other medium that can be used to store computer-executable code in the form of instructions or data structures and that can be accessed by a computer.

Fig. 1 is a diagram illustrating an example of a wireless communication system and an access network 100. A wireless communication system, also referred to as a Wireless Wide Area Network (WWAN), includes a base station 102, a UE104, and an Evolved Packet Core (EPC) 160. Base station 102 may include a macro cell (high power cellular base station) and/or a small cell (low power cellular base station). The macro cell includes an eNB. Small cells include femtocells, picocells and microcells.

The base stations 102, collectively referred to as evolved Universal Mobile Telecommunications System (UMTS) terrestrial radio access network (E-UTRAN), interface with the EPC 160 through backhaul links 132 (e.g., the S1 interface). Among other functions, the base station 102 may perform one or more of the following functions: transmission of user data, radio channel encryption and decryption, integrity protection, header compression, mobility control functions (e.g., handover, dual connectivity), inter-cell interference coordination, connection establishment and release, load balancing, distribution of non-access stratum (NAS) messages, NAS node selection, synchronization, Radio Access Network (RAN) sharing, Multimedia Broadcast Multicast Service (MBMS), user and device tracking, RAN Information Management (RIM), paging, positioning, and delivery of warning messages. Base stations 102 may communicate with each other directly or indirectly (e.g., through EPC 160) through backhaul link 134 (e.g., X2 interface). The backhaul link 134 may be wired or wireless.

The base station 102 may communicate wirelessly with the UE 104. Each of the base stations 102 may provide communication coverage for a respective geographic coverage area 110. There may be overlapping geographic coverage areas 110. For example, a small cell 102 ' may have a coverage area 110 ', the coverage area 110 ' overlapping with the coverage areas 110 of one or more macro base stations 102. A network that includes both small cells and macro cells may be referred to as a heterogeneous network. The heterogeneous network may also include a home evolved node b (enb) (henb), which may provide services to a restricted group referred to as a Closed Subscriber Group (CSG). The communication link 120 between the base station 102 and the UE104 may include Uplink (UL) (also referred to as reverse link) transmissions from the UE104 to the base station 102 and/or Downlink (DL) (also referred to as forward link) transmissions from the base station 102 to the UE 104. The communication link 120 may use MIMO antenna techniques including spatial multiplexing, beamforming, and/or transmit diversity. The communication link may be through one or more carriers. The base station 102/UE 104 may use a spectrum of up to Y MHz (e.g., 5, 10, 15, 20MHz) bandwidth per carrier allocated in a carrier aggregation of up to a total of yxmhz (x component carriers) for transmissions in each direction. These carriers may or may not be adjacent to each other. The carrier allocation may be asymmetric with respect to DL and UL (e.g., more or fewer carriers are allocated for DL than UL). The component carriers may include a primary component carrier and one or more secondary component carriers. The primary component carrier may be referred to as a primary cell (PCell), and the secondary component carrier may be referred to as a secondary cell (SCell).

The wireless communication system may also include a Wi-Fi Access Point (AP)150 that communicates with a Wi-Fi base Station (STA)152 via a communication link 154 in a 5GHz unlicensed spectrum. When communicating in the unlicensed spectrum, STA 152/AP 150 may perform a Clear Channel Assessment (CCA) prior to the communication to determine whether the channel is available.

The small cell 102' may operate in licensed spectrum and/or unlicensed spectrum. When operating in unlicensed spectrum, the small cell 102' may employ LTE and use the same 5GHz unlicensed spectrum as used by the Wi-Fi AP 150. A small cell 102' employing LTE in unlicensed spectrum may improve coverage and/or increase capacity of an access network. LTE in unlicensed spectrum may be referred to as unlicensed LTE (LTE-U), Licensed Assisted Access (LAA), or MuLTEfire.

The EPC 160 may include a Mobility Management Entity (MME)162, other MMEs 164, a serving gateway 166, a Multimedia Broadcast Multicast Service (MBMS) gateway 168, a broadcast multicast service center (BM-SC)170, and a Packet Data Network (PDN) gateway 172. MME 162 may communicate with Home Subscriber Server (HSS) 174. MME 162 is a control node that handles signaling between UE104 and EPC 160. Generally, the MME 162 provides bearer and connection management. All user Internet Protocol (IP) packets are transported through the serving gateway 166, which serving gateway 166 is itself connected to the PDN gateway 172. The PDN gateway 172 provides UE IP address allocation as well as other functions. The PDN gateway 172 and BM-SC 170 are connected to an IP service 176. IP services 176 may include the internet, intranets, IP Multimedia Subsystem (IMS), PS streaming services (PSs), and/or other IP services. The BM-SC 170 may provide functionality for MBMS user service provisioning and delivery. The BM-SC 170 may serve as an entry point for content provider MBMS transmissions, may be used to authorize and initiate MBMS bearer services within a Public Land Mobile Network (PLMN), and may be used to schedule MBMS transmissions. The MBMS gateway 168 may be used to distribute MBMS traffic to base stations 102 belonging to a Multicast Broadcast Single Frequency Network (MBSFN) area broadcasting a particular service and may be responsible for session management (start/stop) and collecting eMBMS-related charging information.

A base station may also be called a node B, an evolved node B (enb), an access point, a base transceiver station, a wireless base station, a wireless transceiver, a transceiver function, a Basic Service Set (BSS), an Extended Service Set (ESS), or some other suitable terminology. Base station 102 may provide an access point for UE104 to EPC 160. Examples of UEs 104 include cellular phones, smart phones, Session Initiation Protocol (SIP) phones, laptops, Personal Digital Assistants (PDAs), satellite radios, global positioning systems, multimedia devices, video devices, digital audio players (e.g., MP3 players), cameras, game consoles, tablet computers, smart devices, wearable devices, or any other similarly functioning device. UE104 may also be referred to as a station, mobile station, subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, mobile device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, wireless terminal, remote terminal, handset, user agent, mobile client, or some other suitable terminology.

Referring again to fig. 1, in certain aspects, the UE104 may include a DRX component 198 configured to determine how to handle bundled M-PDCCH candidates that partially overlap with DRX on durations and/or determine DRX configuration parameters. In other aspects, the UE104 may include an SPS component 199 configured to adjust DRX reception or transmission when subframes granted by SPS are not available.

Fig. 2A is a diagram 200 showing an example of a DL frame structure in LTE. Fig. 2B is a diagram 230 showing an example of channels in a DL frame structure in LTE. Fig. 2C is a diagram 250 illustrating an example of a UL frame structure in LTE. Fig. 2D is a diagram 280 illustrating an example of channels in a UL frame structure in LTE. Other wireless communication technologies may have different frame structures and/or different channels. In LTE, a frame (10ms) may be divided into 10 equally sized subframes. Each subframe may include two consecutive slots. A resource grid may be used to represent two slots, each slot including one or more time concurrent Resource Blocks (RBs) (also referred to as physical RBs (prbs)). The resource grid is divided into a plurality of Resource Elements (REs). In LTE, for a conventional cyclic prefix, an RB contains 12 consecutive subcarriers in the frequency domain and 7 consecutive symbols in the time domain (OFDM symbols for DL; SC-FDMA symbols for UL), for a total of 84 REs. For an extended cyclic prefix, an RB contains 12 consecutive subcarriers in the frequency domain and 6 consecutive symbols in the time domain, for a total of 72 REs. The number of bits carried by each RE depends on the modulation scheme.

As shown in fig. 2A, some of the REs carry DL reference (pilot) signals (DL-RS) used for channel estimation at the UE. The DL-RS may include cell-specific reference signals (CRS) (also sometimes referred to as common RS), UE-specific reference signals (UE-RS), and channel state information reference signals (CSI-RS). Fig. 2A shows CRSs (indicated as R, respectively) for antenna ports 0, 1, 2 and 3₀、R₁、R₂And R₃) UE-RS (indicated as R) of antenna port 5₅) And CSI-RS (indicated as R) for antenna port 15. Fig. 2B shows an example of various channels in a DL subframe of a frame. The Physical Control Format Indicator Channel (PCFICH) is in symbol 0 of slot 0 and carries a Control Format Indicator (CFI) indicating whether the Physical Downlink Control Channel (PDCCH) occupies 1, 2 or 3 symbols (fig. 2B shows a PDCCH occupying 3 symbols). The PDCCH carries Downlink Control Information (DCI) in one or more Control Channel Elements (CCEs), each CCE includes nine RE groups (REGs), each REG including four consecutive REs in one OFDM symbol. The UE may be configured with a UE-specific enhanced pdcch (epdcch) that also carries DCI. The ePDCCH may have 2,4, or 8 RB pairs (fig. 2B shows two RB pairs, each subset including one RB pair). A physical hybrid automatic repeat request (ARQ) (HARQ) indicator channel (PHICH) is also in symbol 0 of slot 0 and carries HARQ Indicators (HIs) indicating HARQ Acknowledgement (ACK)/negative ACK (nack) feedback based on a Physical Uplink Shared Channel (PUSCH). The Primary Synchronization Channel (PSCH) is in symbol 6 of slot 0 in subframes 0 and 5 of the frame and carries the Primary Synchronization Signal (PSS) that is used by the UE to determine subframe timing and physical layer identity. The Secondary Synchronization Channel (SSCH) is in symbol 5 of slot 0 in subframes 0 and 5 of the frame and carries a Secondary Synchronization Signal (SSS) that is used by the UE to determine the physical layer cell identification group number. Based on the physical layer identity and the physical layer cell identity group number, the UE is able to determine a Physical Cell Identifier (PCI). Based on the PCI, the UE can determine the location of the DL-RS. Physical Broadcast Channel (PBCH) in symbols 0, 1, 2, 3 of slot 1 of subframe 0 of a frameAnd carries a Master Information Block (MIB). The MIB provides the number of RBs, PHCIH configuration, and System Frame Number (SFN) in the DL system bandwidth. The Physical Downlink Shared Channel (PDSCH) carries user data, broadcast system information such as System Information Blocks (SIBs) that are not transmitted through the PBCH, and paging messages.

As shown in fig. 2C, some of the REs carry demodulation reference signals (DM-RS) for channel estimation at the eNB. The UE may additionally transmit a Sounding Reference Signal (SRS) in the last symbol of the subframe. The SRS may have a comb structure, and the UE may transmit the SRS on one of the comb teeth. SRS may be used by the eNB for channel quality estimation to enable frequency-dependent scheduling on the UL. Fig. 2D shows an example of various channels in the UL subframe of a frame. A Physical Random Access Channel (PRACH) may be configured in one or more subframes in a frame based on the PRACH. The PRACH may include six consecutive RB pairs in a subframe. The PRACH allows the UE to perform initial system access and achieve UL synchronization. The Physical Uplink Control Channel (PUCCH) may be located on the edge of the UL system bandwidth. The PUCCH carries Uplink Control Information (UCI) such as scheduling request, Channel Quality Indicator (CQI), Precoding Matrix Indicator (PMI), Rank Indicator (RI), and harq ack/NACK feedback. The PUSCH carries data and may additionally be used to carry Buffer Status Reports (BSRs), Power Headroom Reports (PHR), and/or UCI.

Fig. 3 is a block diagram of an eNB 310 in communication with a UE 350 in an access network. In the DL, IP packets from EPC 160 may be provided to controller/processor 375. Controller/processor 375 implements layer 3 and layer 2 functions. Layer 3 includes a Radio Resource Control (RRC) layer, and layer 2 includes a Packet Data Convergence Protocol (PDCP) layer, a Radio Link Control (RLC) layer, and a Medium Access Control (MAC) layer. Controller/processor 375 provides RRC layer functions associated with broadcast of system information (e.g., MIB, SIBs), RRC connection control (e.g., RRC connection paging, RRC connection establishment, RRC connection modification, and RRC connection release), inter-Radio Access Technology (RAT) mobility, and measurement configuration of UE measurement reports; PDCP layer functions associated with header compression/decompression, security (ciphering, deciphering, integrity protection, integrity verification) and handover support functions; RLC layer functions associated with transmission of upper layer Packet Data Units (PDUs), error correction by ARQ, concatenation, segmentation and reassembly of RLC Service Data Units (SDUs), re-segmentation of RLC data PDUs, and re-ordering of RLC data PDUs; and MAC layer functions associated with mapping between logical channels and transport channels, multiplexing of MAC SDUs onto Transport Blocks (TBs), demultiplexing of MAC SDUs from TBs, scheduling information reporting, error correction by HARQ, priority handling, and logical channel prioritization.

The Transmit (TX) processor 316 and the Receive (RX) processor 370 perform layer 1 functions associated with various signal processing functions. Layer 1, which includes the Physical (PHY) layer, may include error detection on transport channels, Forward Error Correction (FEC) encoding/decoding of transport channels, interleaving, rate matching, mapping onto physical channels, modulation/demodulation of physical channels, and MIMO antenna processing. The TX processor 316 processes the mapping to the signal constellation based on various modulation schemes (e.g., Binary Phase Shift Keying (BPSK), Quadrature Phase Shift Keying (QPSK), M-phase shift keying (M-PSK), M-quadrature amplitude modulation (M-QAM)). The coded and modulated symbols may then be split into parallel streams. Each stream may then be mapped to OFDM subcarriers, multiplexed with reference signals (e.g., pilots) in the time and/or frequency domain, and then combined together using an Inverse Fast Fourier Transform (IFFT) to produce a physical channel carrying a stream of time domain OFDM symbols. The OFDM streams are spatially precoded to produce a plurality of spatial streams. The channel estimates from channel estimator 374 may be used to determine coding and modulation schemes, as well as for spatial processing. The channel estimates may be derived from reference signals and/or channel condition feedback transmitted by the UE 350. Each spatial stream may then be provided to a different antenna 320 via a separate transmitter 318 TX. Each transmitter 318TX may modulate an RF carrier with a corresponding spatial stream for transmission.

At the UE 350, each receiver 354RX receives a signal through its respective antenna 352. Each receiver 354RX recovers information modulated on an RF carrier and provides the information to a Receive (RX) processor 356. The TX processor 368 and the RX processor 356 implement layer 1 functions associated with various signal processing functions. The RX processor 356 may perform spatial processing on the information to recover any spatial streams destined for the UE 350. If multiple spatial streams are intended for the UE 350, they may be combined into a single OFDM symbol stream by the RX processor 356. The RX processor 356 then converts the OFDM symbol stream from the time-domain to the frequency domain using a Fast Fourier Transform (FFT). The frequency domain signal includes a separate OFDM symbol stream for each subcarrier in the OFDM signal. The symbols on each subcarrier and the reference signal are recovered and demodulated by determining the most likely signal constellation points transmitted by the eNB 310. These soft decisions may be based on channel estimates computed by channel estimator 358. The soft decisions are then decoded and deinterleaved to recover the data and control signals that were originally transmitted by the eNB 310 on the physical channel. The data and control signals are then provided to a controller/processor 359, which controller/processor 359 implements layer 3 and layer 2 functions.

The controller/processor 359 can be associated with memory 360 that stores program codes and data. The memory 360 may also be referred to as a computer-readable medium. In the UL, controller/processor 359 provides demultiplexing between transport and logical channels, packet reassembly, deciphering, header decompression and control signal processing to recover IP packets from EPC 160. The controller/processor 359 is also responsible for error detection using ACK and/or NACK protocols to support HARQ operations.

Similar to the functionality described in connection with the DL transmission by eNB 310, controller/processor 359 provides RRC layer functions associated with system information (e.g., MIB, SIB) acquisition, RRC connection, and test reporting; PDCP layer functions associated with header compression/decompression and security (ciphering, deciphering, integrity protection, integrity verification); RLC layer functions associated with transmission of upper layer PDUs, error correction by ARQ, concatenation, segmentation and reassembly of RLC SDUs, RLC data PDU re-segmentation and re-ordering of RLC data PDUs; and MAC layer functions associated with mapping between logical channels and transport channels, multiplexing of MAC SDUs onto TBs, demultiplexing of MAC SDUs from TBs, scheduling information reporting, error correction by HARQ, priority handling, and logical channel prioritization.

The TX processor 368 may use channel estimates derived by a channel estimator 358 from a reference signal or feedback transmitted by the eNB 310 to select an appropriate coding and modulation scheme and to facilitate spatial processing. The spatial streams generated by the TX processor 368 may be provided to different antennas 352 via separate transmitters 354 TX. Each transmitter 354TX may modulate an RF carrier with a corresponding spatial stream for transmission.

UL transmissions are processed at the eNB 310 in a manner similar to that described in connection with the receiver function at the UE 350. Each receiver 318RX receives a signal through its respective antenna 320. Each receiver 318RX recovers information modulated on an RF carrier and provides the information to RX processor 370.

The controller/processor 375 can be associated with a memory 376 that stores program codes and data. The memory 376 may be referred to as a computer-readable medium. In the UL, the controller/processor 375 provides demultiplexing between transport and logical channels, packet reassembly, deciphering, header decompression, control signal processing to recover IP packets from the UE 350. IP packets from the controller/processor 375 may be provided to the EPC 160. The controller/processor 375 is also responsible for error detection using ACK and/or NACK protocols to support HARQ operations.

A low cost MTC UE that the category 0UE may comprise. MTC UEs may be implemented with a reduced peak data rate (e.g., up to 1000 bits for one transport block size). Furthermore, MTC UEs may be restricted to support rank 1 transmission and/or have 1 receive antenna. According to the LTE standard, when MTC UEs are half-duplex, MTC UEs may have more relaxed switching timing (switching from transmission to reception or from reception to transmission) compared to legacy or non-MTC UEs. For example, non-MTC UEs may have a switching time on the order of 20 microseconds, while MTC UEs may have a switching time on the order of 1 millisecond.

MTC UEs may monitor the DL control channel in the same manner as non-MTC UEs, e.g., monitor a wideband signal, monitor both PDCCH and EPDCCH, etc. Additional MTC enhancements may be supported. While MTC UEs operate in a narrow band, MTC UEs are also capable of operating in a wider system bandwidth (e.g., 1.4/3/5/10/15/20 MHz). For example, an MTC UE may operate in a system bandwidth of 1.4MHZ and may use 6 Resource Blocks (RBs). Furthermore, MTC UEs may have enhanced coverage of up to 15 dB.

In eMTC with extended coverage support, one or more channels may be bundled (e.g., repeated) in the time domain. In particular, the bundled M-PDCCH may be transmitted using multiple subframes. The eNB may allocate resources for the M-PDCCH according to the requirements for the ePDCCH in the narrowband in which the MTC UE operates.

The eNodeB may configure the M-PDCCH with a repetition level. For example, an M-PDCCH with repetition level 2 may be repeated in 2 consecutive subframes. The M-PDCCH with repetition level 4 is repeated in 4 consecutive subframes. The repeated bits may be identical. However, different scrambling sequences may be used for the repetition. The MTC UE may need to receive each of the repetitions or most of the repetitions in order to reliably decode the M-PDCCH. Thus, the MTC UE monitors the M-PDCCH with repetition level 2 every 2 subframes and monitors the M-PDCCH with repetition level 4 every 4 subframes. MTC UEs monitoring M-PDCCH candidates for repetition levels 2 and 4 may be indicated as having a configuration R ═ 2, 4.

In addition, data channels such as MTC-PUSCH (M-PUSCH) and MTC-PDSCH (M-PDSCH) may be bundled with a dynamic length. For example, the eNodeB may indicate in the M-PDCCH that the M-PUSCH has a repetition level of 15 and the M-PDSCH has a repetition level of 13. Static TTI bundling may be used for PUSCH.

Not all subframes may be available for reception or transmission at the MTC UE. Thus, the eNB may be configured to signal a pattern of available subframes in the uplink and downlink. This may result in the starting subframe for M-PDCCH monitoring not being aligned with the radio frame boundary. Sometimes, the DRX on duration may only partially overlap with a bundled M-PDCCH subframe, a CSI reference subframe, or a subframe in an SPS grant.

As such, there is a need for improved techniques for SPS and DRX procedures that can fit multiple subframes and address these partially overlapping scenarios.

MTC and DRX

In the M-PDCCH region of a DL radio subframe, there may be many locations where a specific M-PDCCH is located. To acquire the M-PDCCH, the MTC UE may search for all possible locations. The possible locations of the M-PDCCH differ depending on whether the M-PDCCH is UE-specific or common and also depending on the aggregation level used. All possible locations of the M-PDCCH may be referred to as a search space, and each possible location may be referred to as an M-PDCCH candidate. In addition, if the M-PDCCH is bundled, the search space may include more than one subframe.

To reduce terminal power consumption, the LTE standard includes mechanisms for DRX. To perform DRX, the UE and the network may negotiate awake window periods during which the UE may power on a receiver to allow data transmission with the network. Outside the awake window period, the UE may turn off the receiver and enter a low or zero power state to conserve battery life. Using the configured DRX period, the MTC UE may monitor downlink control signaling only in subframes of the DRX on duration per DRX cycle, sleeping with the receiver circuitry turned off (or in reduced consumption mode) in the remaining subframes. Turning off the receiver for longer periods of the DRX cycle provides greater power savings.

Subframes of bundled M-PDCCH candidates may only partially overlap with DRX on duration or may fall completely outside DRX on duration.

Fig. 4 is a diagram 400 illustrating a DRX on duration of an MTC UE and a configuration of a plurality of M-PDCCH candidates. In this example, as shown, subframes 422, 424, 426, 428 are 4 consecutive subframes in the time domain. Further, the MTC UE may be configured with a DRX on duration that overlaps with one or more subframes in a DRX cycle. In this example, DRX on duration 410 overlaps with 2 subframes (e.g., subframe 422 and subframe 424).

The M-PDCCH candidate a402 with repetition level 2 includes a subframe 422 and a subframe 424, and thus is located entirely in the DRX on 410.

M-PDCCH candidate B404 with repetition level 2 includes subframe 426 and subframe 428. M-PDCCH candidate B404 falls entirely outside DRX on 410.

M-PDCCH candidate C406 with repetition level 4 includes subframes 422, 424, 426, 428. Thus, M-PDCCH candidate C406 is partially located in DRX on 410 (for subframes 422 and 424) and partially falls outside DRX on 410 (for subframes 426 and 428).

Fig. 5 is a diagram 500 illustrating another exemplary configuration of a DRX on duration and a plurality of M-PDCCH candidates for an MTC UE. In this example, subframes 522, 524, 526, 528 are 4 consecutive subframes in the time domain, as shown. Further, in this example, DRX on duration 510 overlaps with 2 subframes (e.g., subframe 524 and subframe 526). In contrast to the example in fig. 4, the start of the DRX on duration 510 is offset with respect to the starting subframe of the M-PDCCH candidate.

M-PDCCH candidate a 502 with repetition level 2 includes subframe 522 and subframe 524. The M-PDCCH candidate B504 with repetition level 2 includes a subframe 526 and a subframe 528. M-PDCCH candidate C506 with repetition level 4 includes subframes 522, 524, 526, 528.

In this example, M-PDCCH candidate a 502 is located partially within DRX on duration 510 (e.g., in subframe 524) and partially outside DRX on duration 510 (e.g., in subframe 522). M-PDCCH candidate B504 is located partially within DRX on duration 510 (e.g., in subframe 526) and partially outside DRX on duration 510 (e.g., in subframe 528). M-PDCCH candidate C506 is located partially within DRX on duration 510 (e.g., in subframe 524 and subframe 526) and partially outside DRX on duration 510 (e.g., in subframe 522 and subframe 528).

Thus, in fig. 5, no M-PDCCH candidate is entirely within the DRX on duration. Alternatively, each of the M-PDCCH candidates has at least one subframe located outside the DRX on duration 510.

Fig. 6 shows another example 600 of displaying subframes 622, 624, 636, 628, 630, 632, 634, and 636. DRX on duration 610 spans subframes 624 and 626. Fig. 6 shows a plurality of M-PDCCH candidates having 2 repetitions, i.e., candidate a 601, candidate B602, candidate E605, and candidate F606. Fig. 6 shows a plurality of M-PDCCH candidates with 4 repetitions, i.e., candidate C603, candidate G607. Candidate D604 has a repetition of 8 subframes.

MTC UEs may be configured in a number of ways in order to address challenges that partially overlap with bundling M-PDCCH candidates and DRX on durations.

Decoding only candidates that are fully in DRX on

In a first example, an MTC UE may be configured to decode only M-PDCCH candidates entirely contained in a DRX on duration. Thus, for the example shown in fig. 4, the MTC UE may decode M-PDCCH candidate a402 because the set of subframes (e.g., subframe 422 and subframe 424) carrying M-PDCCH candidate a402 are located entirely within DRX on duration 410. The MTC UE may refrain from decoding M-PDCCH candidate B404 and M-PDCCH candidate C406 because the set of subframes carrying these M-PDCCH candidates B704 extend beyond the DRX on duration 410. For the example shown in fig. 5, the MTC UE will not decode any of the M-PDCCH candidates 503, 504, 506 because they each include at least one subframe that is outside the DRX on duration 510. In fig. 6, the UE will not decode any of the M-PDCCH candidates because none fall completely in DRX on 610.

Decoding candidates partially in DRX on

In a second example, an MTC UE may be configured to decode an M-PDCCH candidate having subframes at least partially located in a DRX on duration.

The MTC UE may be configured to decode only M-PDCCH candidates that start in DRX on duration 410 and are at least partially located in DRX on duration 410. Thus, for the example shown in fig. 4, the MTC UE may decode M-PDCCH candidate a402 and M-PDCCH candidate C406. The set of subframes carrying M-PDCCH candidate a402 and M-PDCCH candidate C406 both start in DRX on duration 410 (e.g., at subframe 422). The MTC UE may refrain from decoding M-PDCCH candidate B404 because the set of subframes carrying M-PDCCH candidate B404 does not start in the DRX on duration and does not partially overlap with DRX on duration 410. For the example shown in fig. 5, the MTC UE may decode M-PDCCH candidate B504. The set of subframes carrying M-PDCCH candidate B504 starts in DRX on duration 510 (e.g., at subframe 526) and partially lies in DRX on duration 510. The MTC UE may refrain from decoding M-PDCCH candidate a 502 and M-PDCCH candidate C506 because the set of subframes carrying M-PDCCH candidate a 502 and M-PDCCH candidate C506 both start outside DRX on duration 510. In fig. 6, the UE will only decode candidate B602, which starts in DRX on 610.

The MTC UE may alternatively be configured to decode only M-PDCCH candidates that end in the DRX on duration and are located at least partially in the DRX on duration. Thus, for the example shown in fig. 4, the MTC UE may decode M-PDCCH candidate a402 because the set of subframes carrying M-PDCCH candidate a402 ends in DRX on duration 410 (e.g., at subframe 424). The MTC UE may refrain from decoding M-PDCCH candidate B404 and M-PDCCH candidate C406 because the set of subframes carrying these M-PDCCH candidates C both end outside DRX on duration 410. For the example shown in fig. 5, the MTC UE may decode M-PDCCH candidate a 502 because the set of subframes carrying M-PDCCH candidate a 502 ends in DRX on duration 510 (e.g., at subframe 524). The MTC UE may refrain from decoding M-PDCCH candidate B504 and M-PDCCH candidate C506 because the set of subframes carrying these M-PDCCH candidate B804 ends outside DRX on duration 510. In fig. 6, the UE will only decode candidate a 601, which ends during DRX on 610.

The MTC UE may instead be configured to decode any M-PDCCH candidate located at least partially in the DRX on duration. Thus, for the example shown in fig. 4, the MTC UE may decode M-PDCCH candidate a402 and M-PDCCH candidate C406. The set of subframes carrying both M-PDCCH candidate a402 and M-PDCCH candidate C406 both lie at least partially in DRX on duration 410. The MTC UE may refrain from decoding M-PDCCH candidate B404 because the set of subframes carrying M-PDCCH candidate B404 is not located at least partially in the original DRX on duration 410. For the example shown in fig. 5, the MTC UE may decode each of M-PDCCH candidate a 502, M-PDCCH candidate B504, and M-PDCCH candidate C506 because these M-PDCCH candidates each include at least one subframe located in DRX on 510. In fig. 6, the UE may decode each of candidate a 601, candidate B602, candidate C603, and candidate D604.

The MTE UE may be configured to select among a plurality of candidates that at least partially overlap with the DRX on duration. For example, if the respective sets of subframes carrying each of the plurality of M-PDCCH candidates are of the same length and are at least partially in the DRX on duration, the MTC UE may be configured to select one or more of the plurality of M-PDCCH candidates for decoding based on a rule. The rule may cause the UE to select a first M-PDCCH candidate or may cause the UE to select an M-PDCCH candidate with a greater amount of overlap with the DRX on duration. For example, in fig. 6, the UE may select one of candidate a 601, candidate B602, candidate C603, and candidate D604.

Extending DRX on duration

In a third example, an MTC UE may be configured to extend the beginning or end of a DRX on duration in order to decode M-PDCCH candidates carried by a set of subframes that are at least partially in the original DRX on duration. Furthermore, any M-PDCCH candidate in the extended DRX on duration, which is also carried by the set of subframes, may also be decoded by the MTC UE.

Thus, for the example shown in fig. 4, the MTC UE may decode M-PDCCH candidate a402 and M-PDCCH candidate C406. M-PDCCH candidate C406 has subframes 422 and 424 that fall in DRX on 410. Accordingly, the UE may determine to extend DRX on 410 to DRX on 410-2C comprising extended lengths of subframes 426 and 428 such that each of the subframes of M-PDCCH candidate C406 is included in the extended DRX on duration 410-2C. Fig. 6 shows that DRX on 610 may be extended to extended DRX on 601-a to include all subframes of candidate D604, candidate D604 having subframes 624, 626 in original DRX on 610.

The MTC UE may determine that subframes 422, 424, 426, 428 in DRX on duration 410 also carry all subframes of M-PDCCH candidate B404. Thus, the MTC UE may also decode M-PDCCH candidate B404.

For the example shown in fig. 5, the MTC UE partially overlaps with each of the M-PDCCH candidates 502, 504, 506. Accordingly, the MTC UE may extend its DRX on to include a configuration of each of the subframes 522, 524, 526, and 528, and may decode each of the M-PDCCH candidates 502, 504, 506. The end of the DRX on duration may be extended, as in DRX on 510-2A. The start of the DRX on duration may be extended, as in extended DRX on 510-2B. The beginning and end of the DRX on duration may be extended, as in 510-2C.

Inactivity timer

Similar problems may arise with respect to inactivity timers. If the UE decodes PDCCH in a certain subframe, the UE may typically go to DRX after a defined number (e.g., M) of subframes without M-PDCCH decoding. This is called an inactivity timer and the M subframes are considered inactive. In legacy LTE, PDCCH/ePDCCH is not bundled and M may be counted in terms of valid control subframes (i.e., subframes in which the UE can monitor PDCCH). The value may be as small as 1. However, in eMTC, the control channel may use multiple repetitions in multiple subframes. The number of repetitions may be variable, e.g. the UE may need to monitor 2,4,8 repetitions. Therefore, when the UE receives the partially bundled control channel, the UE needs to determine whether to treat partial reception of the M-PDCCH as an inactive subframe. If the UE does not consider partial reception of the M-PDCCH as inactive subframes, the UE must start counting towards M inactive subframes before going to DRX.

Thus, rather than determining whether to decode the M-PDCCH in the example above, the UE may determine whether to treat the M-PDCCH as having been received and reset the inactivity timer.

Aligning DRX on with M-PDCCH monitoring

As described above, the DRX on period may not be aligned with the starting subframe of the M-PDCCH because the M-PDCCH subframe is defined separately from DRX. The UE may resolve the alignment difference in a manner that reduces partially overlapping M-PDCCH subframes. The MTC UE may be configured to start a DRX on duration at an M-PDCCH start subframe (i.e., an initial subframe monitored for the M-PDCCH).

More specifically, for MTC UEs without configured DRX, the MPDCCH start subframe follows the pattern from a given reference subframe. For example, the pattern may be determined based on a repetition level of M-PDCCH candidates monitored by the MTC UE. In one example, the MTC UE monitors M-PDCCH candidates with repetition levels of 2,4, and 8. The MTC UE may determine the pattern based on the maximum repetition level. Accordingly, the MTC UE may start the M-PDCCH monitoring process every eighth subframe starting from a specific subframe (e.g., frame 0, subframe 0).

For MTC UEs with DRX, the M-PDCCH starting subframe follows a pattern from a given reference subframe, which may be the starting subframe of the DRX on duration. If the starting subframe of the DRX on-duration is not valid, the MTC UE will adjust the starting subframe of the DRX on-duration to the next valid or previously valid subframe.

Fig. 7 is a diagram 700 illustrating a DRX on duration and a configuration of an M-PDCCH start subframe for an MTC UE. In this example, an MTC UE without configured DRX and monitoring M-PDCCH with repetition levels of 2,4 and 8 may start the first, second and third M-PDCCH monitoring processes at subframe 0, subframe 8 and subframe 16, respectively. MTC UEs with configured DRX and monitoring M-PDCCH with repetition levels of 2,4 and 8 may start the first, second and third M-PDCCH monitoring procedure at subframe 5, subframe 13 and subframe 21, respectively. In this example, subframe 5 is also the beginning of the DRX on duration for the MTC UE.

DRX parameter as a function of M-PDCCH parameter

The MTC UE may be configured to determine a DRX configuration parameter based on the M-PDCCH configuration. For example, a DRX parameter, such as DRX on duration or other aspects of the DRX cycle, may be defined as a function of a reference subframe set used to carry M-PDCCH candidates having a selected repetition level. For example, when the MTC UE monitors M-PDCCH candidates having repetition levels of 2,4, and 8, the MTC UE may select a subframe set including 8 subframes for carrying the M-PDCCH candidate having repetition level 8 (i.e., the maximum repetition level in this example) as the reference subframe set. The DRX on duration may be configured to a first integer number of starting M-PDCCH monitoring subframes.

In another example, the DRX on duration may be configured with a first number of subframes and the DRX cycle may be configured with a second number of subframes. However, the MTC UE may further adjust the DRX on duration to start at the beginning of the reference set of subframes before, after, or near the original start of the DRX on duration.

Fig. 8 is a diagram 800 illustrating another configuration of DRX on duration and M-PDCCH starting subframe for MTC UEs. In this example, as shown, an MTC UE according to scheme a may be configured with a DRX on duration of 1 reference subframe set and a DRX cycle of 3 reference subframe sets (i.e., a DRX off duration of 2 reference subframe sets). In this example as described above, the reference subframe set includes 8 subframes and starts at subframe 0. Thus, the DRX on duration starts at subframe 0 and ends at subframe 7. The DRX off duration begins at subframe 8 and ends at subframe 23. The DRX on duration then starts again at subframe 24 and lasts 8 subframes.

In this example, an MTC UE according to scheme B may be configured with a DRX on duration of 8 subframes and a DRX cycle of 20 subframes. As described above, the reference subframe set includes 8 subframes and starts at subframe 0. The DRX on duration starts at subframe 0 and ends at subframe 7. According to the DRX configuration, the next DRX on duration should start at subframe 20. In this example, the MTC UE determines that subframe 20 is located in a set of reference subframes beginning at subframe 16 and ending at subframe 23. The MTC UE may determine to start the DRX on duration at the beginning of the current reference subframe set (e.g., at subframe 16). The MTC UE may determine to start the DRX on duration at the beginning of the next reference subframe set (e.g., at subframe 24). Further, the MTC UE may determine to start the DRX on duration at the beginning of the reference subframe set, where the beginning is closest to the beginning of the initial configuration (e.g., subframe 20). In this example, the start of the current subframe set (i.e., subframe 16) and the start of the next subframe set (i.e., subframe 24) have the same distance to the start of the initial configuration (e.g., subframe 20). The MTC UE may select the start of the DRX on duration based on a rule. For example, the MTC UE may select an earlier start (i.e., subframe 16) or may implement an alternative rule (and select a later start (i.e., subframe 24)).

In another example, the M-PDCCH parameter may be used to determine the DRX on duration. MTC UEs may be configured with a DRX on duration timer that uses a PDCCH Subframe (PSF) number to determine a DRX on duration. The PSF number indicates the number of reference subframe sets during which the UE should be awake and monitor PDCCH/ePDCCH as described above. The MTC UE may determine a DRX on duration within which to monitor the M-PDCCH as a function of a repetition level of the M-PDCCH candidate.

For example, the reference subframe set may be determined based on a minimum repetition level, a maximum repetition level, or all repetition levels of M-PDCCH candidates monitored by the mtciue. In this example, when the mtcu monitors M-PDCCH candidates having repetition levels 2,4, and 8, the reference subframe set is based on the maximum repetition level. MTC UEs may be configured with PSF 3. Thus, the MTC UE may determine the DRX on duration as

Maximum repetition level PSF of M-PDCCH when DRX is turned on

In this example, DRX on causes MTC UEs to monitor M-PDCCH for 24 valid subframes (i.e., 3 times 8 subframes) after the start of DRX on duration, which allows mtues to decode 3M-PDCCH candidates with the largest repetition level.

In another example, the DRX on duration timer may be configured with PSF X. The mtcu may interpret that PSF X indicates that the MTC UE decodes at least X number of M-PDCCH candidates. For example, if the MTC UE monitors M-PDCCH candidates with repetition levels 2 and 4, the DRX on duration timer configured with PSF 2 instructs the MTC UE to decode at least 2M-PDCCH candidates (in this example, one with repetition level 2 and one with repetition level 4). As such, the MTC UE remains awake and decodes 4 subframes.

The MTC UE may be configured to: if the MTC UE does not expect permission in the remaining DRX on duration, transition to DRX off mode (sleep) is early. Referring back to fig. 5, the MTC UE monitors M-PDCCH candidate a 502, M-PDCCH candidate B404, and M-PDCCH candidate C506. The MTC UE may perform early detection of M-PDCCH candidate C506 in subframe 504. After successfully decoding M-PDCCH candidate C506, the MTC UE may decide to go to DRX off mode because the MTC UE may determine that M-PDCCH candidate B504 is not present because M-PDCCH candidate B504 completely overlaps M-PDCCH candidate C506.

CSI measurement for MTC using DRX

When the MTC UE is in coverage enhancement mode, the MTC UE may measure reference symbols in a group of reference subframes (e.g., 4, 6, or 8 subframes) to determine CSI feedback. In low SNR and narrowband scenarios, one subframe may not be sufficient to provide accurate CSI measurements. However, it is possible to request the mtcu to provide CSI feedback in one subframe (e.g., subframe N) and one or more subframes of a group of corresponding reference subframes (e.g., subframes (N-7) to (N-4)) to measure are located in the DRX off duration.

Fig. 9 is a diagram 900 illustrating a configuration of a DRX cycle and CSI reference subframe of an MTC UE. In this example, the MTC UE is configured with a continuous DRX on duration 910, DRX off duration 912, and DRX on duration 914. Further, to transmit CSI feedback at a particular subframe, the group of respective reference subframes includes subframes 942, 944, 946, 948. Further, subframe 942 and subframe 944 are in DRX off duration 912. Subframe 946 and subframe 948 are in DRX on duration 914.

In a first example, when some subframes in the group of respective reference subframes are outside the DRX on duration, the MTC UE may wake up early to measure each subframe in the group of respective reference subframes to determine CSI feedback. In fig. 9, the MTC UE may extend the DRX on duration 914 to include a subframe 942 and a subframe 944. Accordingly, the MTC UE may measure subframes 942, 944, 946, 948 to generate CSI feedback.

In a second example, when some subframes in the group of respective reference subframes are outside of the DRX on duration and the DRX off duration does not exceed a threshold (e.g., 4 subframes, 8 subframes), the MTC UE may replace the respective reference subframes in the DRX off duration with the same number of subframes in the previous DRX on duration. In fig. 9, the MTC UE may determine that the DRX off duration 912 does not exceed a threshold. Thus, the MTC UE may select subframes 936 and 938 instead of subframes 942 and 944, with subframes 942 and 944 in the DRX off duration 912. For example, the subframe 936 and the subframe 938 may be the last two subframes in the DRX on duration 910. Accordingly, the MTC UE may measure subframe 936, subframe 938, subframe 946, and subframe 948 to generate CSI feedback.

In a third example, when the group of respective reference subframes partially overlaps with the DRX on duration, the UE may measure subframes within the DRX on duration in the group of respective reference subframes to generate CSI feedback. In fig. 9, the MTC UE may measure subframe 946 and subframe 948 to generate CSI feedback, the subframe 946 and subframe 948 being in DRX on duration 914.

In a fourth example, the MTC UE may refrain from measuring the reference subframes to generate CSI feedback when the group of respective reference subframes partially overlaps with the DRX on duration. In addition, the MTC UE may refrain from sending CSI feedback or may send a default or previous CSI value. In this example, when a group of respective reference subframes partially overlaps with the DRX on duration, the MTC UE determines a percentage of subframes in the group in the DRX off duration. Further, if the percentage exceeds a threshold, the MTC UE may decide not to measure the reference subframe to generate CSI feedback. For example, if a group of respective reference subframes includes 4 subframes, the MTC UE measures subframes in DRX on duration when there are 2 or more subframes in the group in the DRX on duration.

The MTC UE may determine the number of subframes as described above based on an absolute number of subframes or a number of valid subframes. Further, the MTC UE may determine various subframe numbers using various combinations of absolute subframe numbers and valid subframe numbers. For example, the MTC UE may determine a starting subframe of the DRX on duration using the absolute subframe number and may determine the DRX on duration using the valid subframe number (DRX on duration timer).

SPS for MTC using DRX

In another aspect, the eNB may schedule DL or UL transmissions with the MTC UE using SPS. The eNB typically sends the RRC configuration using SPS. The UE receives an SPS activation grant and then transmits or receives according to the grant until an SPS deactivation grant is received or a maximum number of null packets are transmitted. SPS may be configured with different periodicity. As described above, MTC UEs may be half-duplex and may operate in a narrow band. Thus, in some cases, after activating SPS, the MTC UE may not be able to continuously monitor the M-PDCCH to detect SPS deactivation messages or other types of signaling.

For example, an MTC UE may be configured with an M-PUSCH bundling size of 20 subframes and an M-PDCCH bundling size of also 20 subframes. The UL SPS parameters may configure an M-PUSCH transmission period of 30 subframes. That is, the MTC UE transmits M-PUSCH every 30 subframes (e.g., starting in subframe 0, subframe 30, subframe 60 …). As such, the gap between two consecutive M-PUSCH transmissions is 10 subframes (e.g., subframes 20-29). The MTC UE may decode the M-PDCCH using the gap. In this example, the M-PDCCH bundling size is 20 subframes, and the gap between M-PUSCH transmissions does not provide sufficient time for MTC UEs to decode the M-PDCCH bundling size of 20 subframes. Thus, the MTC UE may not be able to receive the SPS deactivation message sent on the M-PDCCH. This problem may also occur in the case of UL SPS or DL/UL SPS.

To address these issues, the eNB scheduler may be implemented to select SPS parameters that provide a sufficient period of time for decoding an M-PDCCH bundle between two SPS transmissions. SPS parameters such as SPS period and UL (or DL) of the transmission bundling size may be determined based on the desired bundling size, bundling size of the M-PDCCH, M-PDCCH starting subframe, and SPS parameters of the DL (or UL).

In another example, the MTC UE may interpret SPS parameters (e.g., periodicity) received from the eNodeB as a function of the bundling size of one or more channels. For example, when the SPS parameters indicate an M-PUSCH period of 10 subframes and an M-PUSCH bundling size of 1 subframe, the MTC UE may determine that the M-PUSCH period to use is 10 subframes (i.e., 10 times 1). When the SPS parameters indicate an M-PUSCH period of 10 subframes and an M-PUSCH bundling size of 4 subframes, the MTC UE may determine that the M-PUSCH period to use is 40 subframes (i.e., 10 times 4). As such, the gap between two SPS transmissions may provide sufficient time for the MTC UE to decode the M-PDCCH.

Furthermore, the MTC UE may not monitor the M-PDCCH when transmitting SPS M-PUSCH or receiving M-PDSCH.

Invalid subframe

In yet another aspect, when the MTC UE uses SPS, the subframe for which the MTC UE receives SPS grants may not be available for UL/DL transmissions.

To address this issue, the MTC UE may defer scheduled transmissions for the unavailable subframes. For example, a bundled transmission between the MTC UE and the eNB may be allocated with subframes 0, 1, and 2. In this example, subframe 1 may not be available due to SPS transmissions. The UE may defer transmission allocated for subframes 1 and 2 to subframes 2 and 3. That is, the transmitter transmits the bundle at subframes 0, 2, and 3, rather than transmitting at subframes 0, 1, and 2.

In another example, the MTC UE may discard transmissions assigned with unavailable subframes. For example, a bundled transmission between the MTC UE and the eNB may be allocated with subframes 0, 1, and 2. Subframe 1 is not available due to SPS transmissions. The UE may therefore discard the transmission allocated for subframe 1. That is, the MTC UE transmits at subframes 0 and 2 instead of subframe 1. Further, the MTC UE may dynamically reduce the repetition level based on the discarded subframes. For example, if the repetition level is 8 and the MTC UE discards 2 subframes, the MTC UE now assumes a repetition of 6.

In another example, an MTC UE may discard an entire transmission when a subframe allocated for the transmission is unavailable. For example, a bundled transmission between the MTC UE and the eNB may be allocated with subframes 0, 1, and 2. Subframe 1 is not available due to SPS transmissions. The MCT UE may therefore discard the entire transmission. That is, the MTC UE does not transmit at any of subframes 0, 1, or 2.

MTC UEs may choose among these different schemes. For example, an MTC UE may determine to drop an entire transmission when an initial (first) subframe allocated for the transmission is unavailable. The MTC UE may defer transmission for the unavailable subframe and the subsequent subframe allocation if the subsequent subframe allocated for the transmission is not available. Alternatively, the MTC UE may discard the transmission for the unavailable subframe allocation. For example, a bundled transmission between an MTC UE and an eNodeB may be allocated with subframes 0, 1, and 2. If subframe 1 is unavailable, the MTC UE may drop the transmission in subframe 1. If subframe 0 is unavailable, the MTC UE may discard the entire transmission.

In another example, the MTC may select one of these examples with respect to unbundled transmissions or small bundled (e.g., less than 3 or 5 subframes) transmissions. The MTC UE may select different examples for large bundled (e.g., more than 4 subframes) transmissions.

HARQ ID determination

For UL HARQ, the HARQ process ID assigned to a particular M-PUSCH may be determined based on the M-PDCCH occasion (transmission) in which the particular M-PUSCH is scheduled. For example, when an MTC UE has 2 HARQ processes (HARQ process 0 and HARQ process 1), every other M-PDCCH occasion is associated with HARQ process 0 or HARQ process 1. If the M-PDCCH occasion occurs every 10 subframes from subframe 0, the M-PUSCH granted by the M-PDCCH in subframes 0-9 and 20-29 uses HARQ process 0. HARQ process 1 is used by the M-PUSCH granted by the M-PDCCH in subframes 10-19 and subframes 30-39.

Further, after the MTC UE is configured with M-PUSCH SPS, the MTC UE does not receive M-PDCCH during the SPS period. The MTC UE may determine a virtual M-PDCCH occasion (transmission) that may have scheduled an M-PUSCH. For M-PUSCH starting at subframe N, a corresponding virtual M-PDCCH occasion may be determined to start at subframe N-k, where k is the scheduling timing (e.g., 4 subframes). The UE then uses the virtual M-PDCCH occasion to determine the HARQ process ID assigned to the particular M-PUSCH as described above. Further, in one example, the MTC UE may count only valid subframes. In another example, the MTC UE may count all subframes.

Alternatively, the above techniques may be modified such that the HARQ process ID for a particular M-PUSCH is determined based on the starting or ending point of the M-PUSCH.

Fig. 10 is a flow chart 1000 of a method of wireless communication. The method may be performed by a UE (e.g., UE104, device 1702/1702'). At 1002, the UE determines a DRX on duration. For example, the DRX on duration may be determined based on communication between the UE and the eNB regarding an awake window during which the UE powers on a receiver to monitor a control channel and allow data transmission with the network.

At 1004, the UE determines a set of subframes that carry the first bundled M-PDCCH candidate, the set of subframes comprising a plurality of subframes. In eMTC, for example, a channel may be bundled to include multiple repetitions in the time domain. For example, the M-PDCCH may have a repetition level of 2 (repeated in 2 consecutive subframes), a repetition level of 4 (repeated in 4 consecutive subframes), and so on. For example, any of the M-PDCCH candidates a-G in fig. 4-6 is an example of a first M-PDCCH candidate for which a set of subframes may be determined by the UE.

At 1006, the UE determines that the DRX on duration at least partially overlaps with the set of subframes. Fig. 4-6 illustrate examples of bundled M-PDCCH candidates that at least partially overlap with DRX on durations. For example, in fig. 4, the UE may determine that DRX on duration 410 overlaps the entire candidate a402 and partially overlaps candidate C406. Fig. 5 and 6 illustrate other examples of potential overlap between DRX on duration and M-PDCCH candidates that may be determined by the UE.

The UE may perform any of a number of actions in order to address potential partial overlap of the M-PDCCH. At 1008, the UE may refrain from decoding the first bundled M-PDCCH candidate. This may occur, for example, when the UE determines that at least a portion of the M-PDCCH candidates are outside the DRX on duration.

As another aspect, the UE may decode the first bundled M-PDCCH candidate at 1010. The UE may decode the first bundled M-PDCCH candidate, for example, when the M-PDCCH candidate is fully located in the DRX on duration or when the first M-PDCCH candidate is at least partially located in the DRX on duration. The determination as to whether to decode or refrain from decoding the first M-PDCCH candidate may be based on additional determinations made by the UE, e.g., as shown in fig. 11 and/or 12.

As a third scheme, the UE may extend the DRX on duration to include the entire set of subframes at 1012, and then decode the first bundled M-PDCCH candidate carried in the set of subframes in the extended DRX on duration at 1014.

Fig. 11 illustrates an example flow diagram 1100 of optional additional aspects that may be performed as part of the method of flow diagram 1000. As in fig. 10, the UE determines a DRX on duration at 1002 and determines a set of subframes carrying the first bundled M-PDCCH candidate at 1004. Once the UE determines at 1006 that the DRX on duration at least partially overlaps with the set of subframes, the UE may determine at 1102 whether a plurality of subframes of the first bundled M-PDCCH candidate are fully within the DRX on duration, for example, by determining whether any subframes of the bundled M-PDCCH candidate are outside of the DRX on duration. The UE may decode the first bundled M-PDCCH candidate if all of the plurality of subframes of the first bundled M-PDCCH candidate are located in the DRX on duration, as shown at 1010 in fig. 10 and 11. Based on this, the UE may determine, for example, to decode candidate a in fig. 4 that is entirely within DRX on duration 410.

If at least one of the plurality of subframes of the first bundled M-PDCCH candidate is outside the DRX on duration, the UE may refrain from decoding the first bundled M-PDCCH candidate at 1008, as shown in fig. 10 and 11. Thus, the UE may refrain from decoding candidate C in fig. 4, which only partially overlaps DRX on duration 410. The UE may also refrain from decoding candidate B in fig. 4, which is completely outside the DRX on duration 410. The determination at 1102 may be made without extending the DRX on duration.

Sometimes, there may be multiple bundled M-PDCCH candidates. At 1104, the UE may determine to monitor one of a plurality of bundled M-PDCCH candidates. For example, in addition to determining a set of subframes carrying a first bundled M-PDCCH candidate, the UE may also determine a set of subframes carrying a second bundled M-PDCCH candidate. For example, fig. 4-6 illustrate that there may be multiple M-PDCCH candidates, e.g., candidates a-G. The UE may determine to monitor the first bundled M-PDCCH candidate based at least on an overlap between the DRX on duration and a set of subframes of the first bundled M-PDCCH candidate. For example, the UE may select bundled M-PDCCH candidates that are in DRX on duration for each subframe. Thus, in fig. 4, the UE may choose to decode candidate a instead of candidate C because candidate a has subframes that are all located in DRX on duration 410, while candidate C has subframes that are located outside DRX on duration. Once this determination is made, the UE decodes the selected M-PDCCH candidate at 1010.

Fig. 12 illustrates another example flow diagram 1200 of optional additional aspects that may be performed as part of the method of flow diagram 1000. As in fig. 10, at 1002, the UE determines a DRX on duration and, at 1004, determines a set of subframes that carry the first bundled M-PDCCH candidate. The UE then determines at 1006 that the DRX on duration at least partially overlaps with the set of subframes, which the UE can determine, as described in connection with fig. 10. In this example, the subframes of the first bundled M-PDDCH candidate fall partially outside the DRX on duration. For example, once the UE determines at 1006 that the DRX on duration at least partially overlaps with the set of subframes, the UE may determine at 1202 whether the subframe of the first bundling M-PDDCH candidate starts in the DRX on duration. When the subframe of the first bundled M-PDDCH candidate begins in the DRX on duration, the UE may decode the first bundled M-PDDCH candidate at 1010. Thus, in fig. 4, the UE may determine both decoding candidate a and candidate C because both candidates start in DRX on duration 410 even though candidate C has subframes outside DRX on 410.

When the subframe does not start in the DRX on duration, the UE may refrain from decoding the first bundled M-PDCCH candidate at 1204. For example, in fig. 5, the UE may determine that subframes of both candidate a and candidate C are outside DRX on 510 and no candidates start in DRX on 510. Thus, the UE may refrain from decoding both candidate a and candidate C.

In another example, the UE may determine at 1206 whether the subframe of the first bundled M-PDDCH candidate ends in the DRX on duration. When the subframe of the first bundled M-PDDCH candidate ends in the DRX on duration, the UE may decode the first bundled M-PDDCH candidate at 1010. When the subframe does not end in the DRX on duration, the UE may refrain from decoding the first bundled M-PDCCH candidate at 1204. According to this example, because candidate a in fig. 5 ends in DRX on 510, the UE may determine to decode candidate a even if candidate a's subframe 522 is outside DRX on 510. The UE may refrain from decoding candidate C in fig. 5 because candidate C ends after DRX on duration 510.

In another example, the UE may decode the first bundled M-PDDCH candidate when any of the subframes of the first bundled M-PDDCH candidate are located in the DRX on duration, e.g., at 1208. In this example, the UE may determine to decode both candidate a and candidate C in fig. 4 and 5 because both candidates have at least one subframe that overlaps with the DRX on 410, 510. In fig. 6, the UE may determine decoding candidate a, candidate C, and candidate D, while suppressing decoding candidate E.

Sometimes, multiple candidates may partially overlap with the DRX on cycle. Thus, at 1210, the UE may determine a set of subframes carrying a second bundled M-PDCCH candidate, wherein subframes of the first bundled M-PDCCH candidate are partially outside of the DRX on duration and subframes of the second bundled M-PDCCH candidate are partially outside of the DRX on duration. The UE may then determine which bundled M-PDCCH candidate to monitor based on the DRX on duration and the overlap between the subframes of the first bundled M-PDCCH candidate and the second bundled M-PDCCH candidate at 1212. At 1214, the UE may decode one of the first bundled M-PDCCH candidate and the second bundled M-PDCCH candidate based on the determination. For example, the UE may select between decoding candidate a and candidate C in fig. 4 and 5. The UE may select between decoding candidate a, candidate C, and candidate D in fig. 6. The determination may be determined based on the DRX on duration and an amount of overlap between subframes of each of the candidates.

Fig. 13 is a flow chart 1300 of a method of wireless communication. The method may be performed by a UE (e.g., UE104, device 1702/1702'). At 1302, the UE determines parameters of bundled M-PDCCH candidates monitored by the UE. As part of the determination of the DRX configuration parameters, the UE may determine a repetition level for each of a plurality of bundled M-PDCCH candidates monitored by the UE, as shown at 1308. The information may be received, for example, from an eNB.

At 1304, the UE receives an indication associated with a DRX configuration of the UE. The indication may include the number of subframes for which the UE should monitor the PDCCH. The indication may be received from an eNB that will transmit the PDCCH.

At 1306, the UE determines a DRX configuration parameter that is a function of the parameter of the M-PDCCH candidate and the indication. The UE may determine a DRX on duration as a function of the indication and a maximum repetition level determination for the plurality of bundled M-PDCCH candidates at 1310. For example, if the UE receives a bundled M-PDCCH parameter with a repetition level of R ═ {2,4,8}, and if the number of subframes for which the UE should monitor the PDCCH is indicated as psf3, e.g., 3 subframes, the UE determines the DRX on duration as a function of the maximum repetition level (i.e., 8) and the indicated number of subframes to monitor (e.g., 3). The function may be, for example,

DRX duration (maximum number of repetitions) PSF (24 subframes)

In this example, the DRX duration may be determined to be 24 subframes and may provide sufficient reception time for decoding 3 candidates with the largest repetition level.

Fig. 14 is a flow diagram 1400 of a method of wireless communication illustrating a DRX cycle of an MTC UE and a configuration of CSI reference subframes. The method may be performed by a UE (e.g., UE104, device 1702/1702'). Sometimes, the UE may need to provide CSI feedback at certain subframes, but the reference subframes may be located outside the DRX on duration.

At 1402, the UE determines a DRX on duration. The determination may be based on communications with the eNB regarding a window for which the UE opens a receiver to receive communications from the eNB. At 1404, the UE determines a group of reference subframes for generating CSI feedback, the group of reference subframes comprising two or more subframes. The determination may be based on information received from the eNB regarding subframes for CSI feedback.

At 1406, the UE determines that the DRX on duration partially overlaps with the group of reference subframes. Fig. 9 shows an example of a corresponding reference subframe that partially overlaps with DRX on 914 and also partially overlaps with DRX off 912. The UE may perform any of a number of actions to account for the partial overlap of the reference subframes.

At 1408, the UE may determine to adjust the DRX on duration to include any reference subframes that fall outside of the DRX on duration. Thus, the UE may wake up outside the DRX on duration to receive the reference subframes outside DRX on. In fig. 9, the UE may wake up early during DRX off 912 to receive subframes 942, 944 of respective reference subframes. Although this example shows subframes beginning before DRX on, when the reference subframe is instead continuing after DRX on has ended, the UE may keep its receiver on at the end of the DRX on period as well.

If the DRX cycle is short enough, the UE may instead use the previous reference subframe, e.g., at 1410. For example, in the second example in fig. 9, the UE may use subframes 936, 938 from the previous DRX on duration 910 in conjunction with 946, 948 in the DRX on 914 to make CSI measurements.

At 1412, the UE may instead use only the portion of the reference subframe located in the DRX on cycle for CSI measurements. Fig. 9 shows this as a third example, where the UE may use only subframes 946 and 948 for CSI measurements during DRX on 914.

At 1414, the UE may refrain from transmitting CSI. For example, the UE may refrain from sending CSI measurements when there is no overlap or only partial overlap. Accordingly, the UE may refrain from sending CSI measurements because reference subframes 942 and 944 are during DRX off 912. The UE may refrain from transmitting CSI when a percentage of the CSI reference subframes that are outside of the DRX on duration exceeds a threshold. If the percentage of the reference subframes that are located in the DRX duration is within the threshold, the UE may determine to transmit CSI using overlapping reference subframes, e.g., as in 1412.

Once the UE performs one of 1408, 1410, 1412, and 1414, the UE may perform CSI measurement using the reference subframe determined at 1408, 1410, 1412, or 1414, and may transmit information regarding the CSI measurement to the eNB.

Fig. 15 is a flow chart 1500 of a method of wireless communication. The method may be performed by a UE (e.g., UE104, device 1702/1702'). At 1502, the UE receives an SPS grant for a set of subframes, the set of subframes including unavailable subframes. The UE may receive an SPS activation grant from the eNB. Some subframes may be invalid subframes that may not be used by the UE for transmission and/or reception.

At 1504, the UE may determine a subset of available subframes in a set of subframes for which the UE receives an SPS grant. For example, after receiving an SPS grant, the UE may consider which subframes in the SPS grant are invalid or unavailable.

At 1506, the UE may adjust reception or transmission during the set of subframes based on the subset of available subframes. The UE may perform any of a number of actions to address the invalid subframes in the SPS grant, e.g., any of 1508, 1510, or 1512. In one example, as part of adjusting reception or transmission at 1508, the UE may defer bundled transmissions scheduled for the unavailable subframe and for any subframes in the set of subframes subsequent to the unavailable subframe at 1508.

In another example, as part of adjusting reception or transmission at 1506, the UE may drop bundled transmissions scheduled for the unavailable subframes at 1510.

In another example, as part of adjusting reception or transmission at 1506, the UE may drop scheduled transmissions including transmissions during unavailable subframes at 1512.

At 1514, the UE may select a scheme to adjust reception or transmission during the set of subframes based on the amount of bundling employed, the scheme including at least one of 1508, 1510, or 1512. Thus, the UE may select between performing 1508, 1510, and 1512 based on the amount of bundling employed.

For example, when the unavailable subframe is the first subframe, the UE may drop scheduled transmissions included during the unavailable subframe at 1510 and may defer bundled transmissions scheduled for the unavailable subframe and (when the unavailable subframe is after the first subframe) for any subframes in the set of subframes after the unavailable subframe at 1508. Thus, the UE may determine whether the unavailable SF is the first subframe at 1516 as part of the selection scheme at 1514.

Fig. 16 is a flow chart 1600 of a method of wireless communication. The method may be performed by a UE (e.g., UE104, device 1702/1702'). The UE may be an MTC UE. At 1602, the UE receives an SPS configuration, e.g., from an eNB. The SPS configuration indicates when the UE should transmit or receive communications with the eNB. When the MTC UE has been configured with M-PUSCH SPS, the MTC UE does not receive M-PDCCH during the configured SPS period.

At 1604, the UE may determine HARQ transmissions according to the SPS configuration. At 1606, the UE determines an M-PDCCH transmission that is omitted for the scheduled HARQ transmission due to the SPS configuration. This may be considered as a virtual M-PDCCH transmission that may have scheduled an M-PUSCH. For example, for M-PUSCH starting at subframe N, the UE may determine the omitted M-PDCCH occasion to start at subframe N + k, k being the scheduling timing. At 1608, the UE determines a HARQ process based on the omitted M-PDCCH transmission. For example, the UE may determine a HARQ process ID assigned to a particular M-PUSCH based on the omitted M-PDCCH occasion. As one example, an MTC UE with 2 HARQ processes would have every other M-PDCCH occasion associated with one of the 2 HARQ processes.

At 1610, the UE transmits a HARQ transmission based on the determined HARQ process.

Fig. 17 is a conceptual data flow diagram 1700 illustrating the data flow between different means/components in an exemplary apparatus 1702. The apparatus may be a UE. The apparatus includes a receiving component 1704 that receives a DL communication from an eNB 1750, the DL communication including, for example, bundled M-PDCCH candidates, DRX configuration parameters, CSI reference signals, and/or the like. The apparatus includes a transmitting component 1706 that transmits UL communications (including CSI measurements, etc.) to eNB 1750. The apparatus may include a DRX component 1708 that determines DRX parameters and processes partially overlapping M-PDCCH subframes. DRX component 1708 may include a DRX on duration component 1710 that determines a DRX on duration, an M-PDCCH subframe component 1712 that determines a set of subframes that carry bundled M-PDCCH candidates, and an overlap component 1714 that determines an overlap between subframes of DRX on duration and subframes of bundled M-PDCCH candidates. DRX component 1708 may also include a decode determination component 1716 that determines whether to decode a bundled M-PDCCH candidate or whether to refrain from decoding a bundled M-PDCCH candidate. The DRX component can include a DRX on extension component 1718 that extends the DRX on duration to include the entire set of subframes. The apparatus 1702 may include a decoding component 1734 configured to decode bundled M-PDCCH candidates, e.g., based on a determination by the decoding determining component 1716 or based on an extension of DRX on duration by the DRX on extension component 1718.

DRX enabling component 1708 may further include an M-PDCCH parameters component 1720 that determines parameters of bundled M-PDCCH candidates monitored by the UE, a DRX indication component 1722 that receives an indication associated with a DRX configuration of the apparatus, and a DRX configuration component 1724 that determines DRX configuration parameters that are a function of the parameters and indications of the M-PDCCH candidates.

The apparatus may include an SPS component 1726 that processes unavailable subframes in an SPS grant. SPS component 1726 may receive SPS grants for a set of subframes. SPS component 1726 may include an available subframes component 1728 that determines a subset of available subframes in the set of subframes, as some of the subframes granted for SPS may not be available. SPS component 1726 may also include an adjustment component 1730 that adjusts reception or transmission during a set of subframes based on a subset of available subframes determined by available subframes component 1728.

The apparatus may also include a CSI component 1732 configured to perform the algorithm described in connection with fig. 14.

The apparatus may include additional components to perform each of the blocks of the algorithm in the flowcharts of fig. 10-16 described above. As such, each block in the flow diagrams of fig. 10-16 described above may be performed by a component, and the apparatus may include one or more of those components. The components may be one or more hardware components specially configured for performing the claimed processes/algorithms, implemented by a processor configured to perform the claimed processes/algorithms, stored in a computer-readable medium for implementation by a processor, or some combination thereof.

Fig. 18 is a diagram 1800 illustrating an example of a hardware implementation of an apparatus 1702' employing a processing system 1814. The processing system 1814 may be implemented with a bus architecture, represented generally by the bus 1824. The bus 1824 may include any number of interconnecting buses and bridges depending on the specific application of the processing system 1814 and the overall design constraints. The bus 1824 links together various circuits including one or more processors and/or hardware components, represented by the processor 1804, the components 1704, 1734, and the computer-readable medium/memory 1806. Although only components 1704, 1706, 1708, 1726, and 1732 are shown in FIG. 18, any of the components 1704 and 1734 may be included in the device 1702'. The bus 1824 may also link various other circuits such as timing sources, peripherals, voltage regulators, and power management circuits, which are well known in the art, and therefore, will not be described any further.

The processing system 1814 may be coupled to a transceiver 1810. The transceiver 1810 is coupled to one or more antennas 1820. The transceiver 1810 provides a means for communicating with various other apparatus over a transmission medium. The transceiver 1810 receives a signal from the one or more antennas 1820, extracts information from the received signal, and provides the extracted information to the processing system 1814 (in particular, the receive component 1704). Additionally, transceiver 1810 receives information from processing system 1814 (and in particular, transmitting component 1706) and generates a signal to apply to one or more antennas 1820 based on the received information. The processing system 1814 includes a processor 1804 coupled to a computer-readable medium/memory 1806. The processor 1804 is responsible for general processing, including the execution of software stored on the computer-readable medium/memory 1806. The software, when executed by the processor 1804, causes the processing system 1814 to perform the various functions described supra for any particular apparatus. The computer-readable medium/memory 1806 may also be used for storing data that is manipulated by the processor 1804 when executing software. The processing system 1814 also includes at least one of the components 1704 and 1734. The components may be software components running in the processor 1804, resident/stored in the computer readable medium/memory 1806, one or more hardware components coupled to the processor 1804, or some combination thereof. The processing system 1814 may be a component of the UE 350 and may include at least one of the TX processor 368, the RX processor 356, and the controller/processor 359, and/or the memory 360.

In one configuration, the means for wireless communication 1702/1702' includes any of the following elements: means for determining a DRX on duration; means for determining a set of subframes that carry bundled M-PDCCH candidates; means for determining an overlap between a DRX on duration and a subframe of an M-PDCCH candidate; means for suppressing decoding; a unit for decoding; means for extending a DRX on duration; means for determining which bundled M-PDCCH candidate to monitor; means for determining parameters for bundling M-PDCCH candidates; means for receiving an indication associated with a DRX configuration of a UE; means for determining DRX configuration parameters; means for receiving an SPS grant; means for determining a subset of available subframes; and means for adjusting reception or transmission. The aforementioned means may be one or more of the aforementioned modules of the apparatus 1702 and/or the processing system 1814 of the apparatus 1702' configured to perform the functions recited by the aforementioned means. As described supra, the processing system 1814 may include the TX processor 368, the RX processor 356, and the controller/processor 359. As such, in one configuration, the aforementioned means may be the TX processor 368, the RX processor 356, and the controller/processor 359 configured to perform the functions recited by the aforementioned means.

It should be understood that the specific order or hierarchy of blocks in the processes/flow diagrams disclosed is merely illustrative of exemplary approaches. It should be understood that the particular order or hierarchy of blocks in the processes/flow diagrams may be rearranged based on design preferences. In addition, some blocks may be combined or omitted. The accompanying method claims present elements of the various blocks in a sample order, and are not meant to be limited to the specific order or hierarchy presented.

The previous description is provided to enable any person skilled in the art to practice the various aspects described herein. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects. Thus, the claims are not intended to be limited to the aspects shown herein, but is to be accorded the full scope consistent with the language claims, wherein reference to an element in the singular is not intended to mean "one and only one" unless specifically so stated, but rather "one or more. The word "exemplary" is used herein to mean "serving as an example, instance, or illustration. Any aspect described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other aspects. The term "some" means one or more unless explicitly stated otherwise. Combinations such as "at least one of A, B or C", "one or more of A, B or C", "A, B, and at least one of C", "one or more of A, B and C", and "A, B, C or any combination thereof" include any combination of A, B and/or C, and may include multiples of a, multiples of B, or multiples of C. In particular, combinations such as "at least one of A, B or C", "one or more of A, B or C", "A, B, and at least one of C", "one or more of A, B and C", and "A, B, C or any combination thereof" may be a only, B only, C, A and B, A and C, B and C only, or a and B and C only, wherein any such combination may comprise one or more members or several members of A, B or C. All structural and functional equivalents to the elements of the various aspects described throughout this disclosure that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the claims. Moreover, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims. The words "module," mechanism, "" element, "" device, "and the like may not be a substitute for the word" unit. As such, no claim element is to be construed as a functional module unless the element is explicitly recited using the phrase "unit for … …".

Claims (28)

1. A method of wireless communication at a user equipment, UE, comprising:

determining discontinuous reception, DRX, and on-duration;

determining a subframe set carrying a plurality of bundled MTC physical downlink control channels, M-PDCCHs, candidates, the subframe set comprising a plurality of subframes;

determining that the DRX on-duration at least partially overlaps the set of subframes, wherein the set of subframes of the plurality of bundled M-PDCCH candidates partially fall outside of the DRX on-duration; and

decoding a first bundled M-PDCCH candidate of the plurality of bundled M-PDCCH candidates if the first bundled M-PDCCH candidate is located in the DRX on-duration.

2. The method of claim 1, further comprising:

determining whether a plurality of subframes of the first bundled M-PDCCH candidate are located in the DRX on-duration.

3. The method of claim 2, wherein the UE decodes the first bundled M-PDCCH candidate if all of the plurality of subframes of the first bundled M-PDCCH candidate are in the DRX on duration; and refrain from decoding the first bundled M-PDCCH candidate by the UE if at least one of the plurality of subframes of the first bundled M-PDCCH candidate is outside the DRX on duration.

4. The method of claim 2, wherein the determination of whether the plurality of subframes of the first bundled M-PDCCH candidate are located in the DRX on duration is made without extending the DRX on duration.

5. The method of claim 1, wherein the plurality of bundled M-PDCCH candidates includes the first bundled M-PDCCH candidate and a second bundled M-PDCCH, the method further comprising:

determining to monitor the first bundled M-PDCCH candidate based at least on the DRX ON duration and an overlap between the subframes of the first bundled M-PDCCH candidate.

6. The method of claim 1, further comprising:

determining to monitor one bundled M-PDCCH candidate of the plurality of bundled M-PDCCH candidates having subframes that are all located in the DRX on-duration.

7. The method of claim 1, wherein if the subframe of the first bundled M-PDCCH candidate partially falls outside of the DRX on duration, the UE decodes the first bundled M-PDCCH candidate when the subframe of the first bundled M-PDCCH candidate starts in the DRX on duration.

8. The method of claim 1, wherein if the subframe of the first bundled M-PDCCH candidate partially falls outside of the DRX on duration, the UE decodes the first bundled M-PDCCH candidate when the subframe of the first bundled M-PDCCH candidate ends in the DRX on duration.

9. The method of claim 1, determining a set of subframes carrying a second bundled M-PDCCH candidate, wherein the subframes of the first bundled M-PDCCH candidate are partially outside the DRX on duration and the subframes of the second bundled M-PDCCH candidate are partially outside the DRX on duration; and

determining which bundling M-PDCCH candidate to monitor based on the DRX ON duration and an overlap between the subframes of the first bundling M-PDCCH candidate and the second bundling M-PDCCH candidate, wherein the UE decodes the first bundling M-PDCCH candidate based on the determination.

10. The method of claim 1, further comprising:

extending the DRX on-duration to include the entire set of subframes, the UE decoding the first bundled M-PDCCH candidate carried in the set of subframes in the extended DRX on-duration.

11. An apparatus for wireless communication at a user equipment, UE, comprising:

means for determining discontinuous reception, DRX, on-duration;

means for determining a set of subframes that carry a plurality of bundled MTC physical downlink control channels, M-PDCCH, candidates, the set of subframes comprising a plurality of subframes;

means for determining that the DRX on-duration at least partially overlaps the set of subframes, wherein the set of subframes of the plurality of bundled M-PDCCH candidates partially falls outside of the DRX on-duration; and

means for decoding a first bundled M-PDCCH candidate of the plurality of bundled M-PDCCH candidates if the first bundled M-PDCCH candidate is located in the DRX on-duration.

12. The apparatus of claim 11, wherein the means for determining that the DRX on duration at least partially overlaps the set of subframes determines whether a plurality of subframes of the first bundled M-PDCCH candidate are located in the DRX on duration.

13. The apparatus of claim 12, wherein the means for decoding decodes the first bundled M-PDCCH candidate if all of the plurality of subframes of the first bundled M-PDCCH candidate are located in the DRX on duration, and refrains from decoding the first bundled M-PDCCH candidate if at least one of the plurality of subframes of the first bundled M-PDCCH candidate are located outside of the DRX on duration.

14. The apparatus of claim 12, wherein the determination of whether the plurality of subframes of the first bundled M-PDCCH candidate are located in the DRX on duration is made without extending the DRX on duration.

15. The apparatus of claim 11, wherein the plurality of bundled M-PDCCH candidates includes the first bundled M-PDCCH candidate and a second bundled M-PDCCH, the apparatus further comprising:

means for determining to monitor the first bundled M-PDCCH candidate based at least on the DRX ON duration and an overlap between the subframes of the first bundled M-PDCCH candidate.

16. The apparatus of claim 11, further comprising:

means for determining to monitor one bundling M-PDCCH candidate of the plurality of bundling M-PDCCH candidates, the one bundling M-PDCCH candidate having subframes that are all located in the DRX on-duration.

17. An apparatus for wireless communication at a user equipment, UE, comprising:

a memory; and

at least one processor coupled to the memory and configured to:

determining discontinuous reception, DRX, and on-duration;

determining a subframe set carrying a plurality of bundled MTC physical downlink control channels, M-PDCCHs, candidates, the subframe set comprising a plurality of subframes;

determining that the DRX on-duration at least partially overlaps the set of subframes, wherein the set of subframes of the plurality of bundled M-PDCCH candidates partially fall outside of the DRX on-duration; and

decoding a first bundled M-PDCCH candidate of the plurality of bundled M-PDCCH candidates if the first bundled M-PDCCH candidate is located in the DRX on-duration.

18. The apparatus of claim 17, in which the at least one processor is further configured:

determining whether a plurality of subframes of the first bundled M-PDCCH candidate are located in the DRX on-duration.

19. The apparatus of claim 18, wherein the at least one processor is configured to:

decoding the first bundled M-PDCCH candidate if all of the plurality of subframes of the first bundled M-PDCCH candidate are located in the DRX on-duration; and

refraining from decoding the first bundled M-PDCCH candidate if at least one of the plurality of subframes of the first bundled M-PDCCH candidate is outside of the DRX on-duration.

20. The apparatus of claim 18, wherein the determination of whether the plurality of subframes of the first bundled M-PDCCH candidate are in the DRX on duration is made without extending the DRX on duration.

21. The apparatus of claim 17, wherein the plurality of bundled M-PDCCH candidates comprises the first bundled M-PDCCH candidate and a second bundled M-PDCCH, and wherein the at least one processor is further configured to:

determining to monitor the first bundled M-PDCCH candidate based at least on the DRX ON duration and an overlap between the subframes of the first bundled M-PDCCH candidate.

22. The apparatus of claim 17, in which the at least one processor is further configured:

determining to monitor one bundled M-PDCCH candidate of the plurality of bundled M-PDCCH candidates having subframes that are all located in the DRX on-duration.

23. A computer-readable medium storing computer executable code for wireless communication at a user equipment, UE, which when executed by a processor causes the processor to:

determining discontinuous reception, DRX, and on-duration;

determining a subframe set carrying a plurality of bundled MTC physical downlink control channels, M-PDCCHs, candidates, the subframe set comprising a plurality of subframes;

determining that the DRX on-duration at least partially overlaps the set of subframes, wherein the set of subframes of the plurality of bundled M-PDCCH candidates partially fall outside of the DRX on-duration; and

decoding a first bundled M-PDCCH candidate of the plurality of bundled M-PDCCH candidates if the first bundled M-PDCCH candidate is located in the DRX on-duration.

24. The computer-readable medium of claim 23, further comprising code for:

determining whether a plurality of subframes of a first bundled M-PDCCH candidate are located in the DRX on-duration.

25. The computer-readable medium of claim 24, further comprising code for:

decoding the first bundled M-PDCCH candidate if all of the plurality of subframes of the first bundled M-PDCCH candidate are located in the DRX on-duration; and

refraining from decoding the first bundled M-PDCCH candidate if at least one of the plurality of subframes of the first bundled M-PDCCH candidate is outside of the DRX on-duration.

26. The computer-readable medium of claim 24, wherein the determination of whether the plurality of subframes of the first bundled M-PDCCH candidate are in the DRX on duration is made without extending the DRX on duration.

27. The computer-readable medium of claim 23, wherein the plurality of bundled M-PDCCH candidates includes the first bundled M-PDCCH candidate and a second bundled M-PDCCH; and further comprising code for:

determining to monitor the first bundled M-PDCCH candidate based at least on the DRX ON duration and an overlap between the subframes of the first bundled M-PDCCH candidate.

28. The computer-readable medium of claim 23, further comprising code for:

determining to monitor one bundled M-PDCCH candidate of the plurality of bundled M-PDCCH candidates having subframes that are all located in the DRX on-duration.

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